Squashable computer runs calculations depending on how you squish it

A computer made using blocks of rubber with streaks of a rubber-silver compound performs simple calculations when squished

By Karmela Padavic-Callaghan

Soft cube-shaped computers can perform different calculations depending on how they are squished. The devices could be used for robots that respond to physical stimuli.

Ryan Harne at Pennsylvania State University and his colleague developed a technique for combining rows of blocks of rubber that have lines of a silver-rubber compound running through them. Different configurations of the blocks act like different circuits, which when combined and connected to electricity make a computer than can perform particular calculations.

In one version of the computer, the team set it up to add together two numbers. A user would then tell the computer which numbers to add by squishing the component blocks to the left or to the right, connecting some of the silver-rubber lines that didn’t touch before in such a way as to encode the numbers in binary. The team connected a (non-squishable) digital display to the computer to show the result of the calculation.

The researchers also created squishy computers that could multiply two numbers or compare them to determine which is greater.

Ryan Hayward at the University of Colorado Boulder says that squishable computers wouldn’t beat conventional computers by being faster or solving harder problems, but they could lead to soft robots that make decisions based on what they touch in their environment, he says.

In the future, Harne imagines a soft computer that is integrated into a building. It could “decide” to repair the building after a crumbling piece of rock applies pressure to it.

Harne says that his team is working on fine-tuning the computer’s “sense of touch” so that it can take inputs beyond the binary, for example by having it encode different squishing strengths into different values.

Journal reference: Nature, DOI: 10.1038/s41586-022-05004-5